Air heater



Patented May ll, i926.

CHARLES J. HANiHAN, F BAYONNE, NEW JERSEY, ASSIGHOR TO THE BiBCOGK'WILCCX GOMPANY, OF BAYONNE, NEW JERSEY, A CORTEORATION OF NEW JERSEY.

AIR HEATER.

Application filed August 9, 1922. Serial No. 580,720.

My present invention relates to heat-transfer devices particularly suchas are used for Fig. 3 is an enlar ement of a portion of llig.

1, and Fig. 4C is a ragrnent showing a modification. 1

Like reference characters indicate like parts in the several views.

In the illustrative embodiment, the hot gases pass through an inlet intoa iiue 11 and outthrough an :outlet 12. The flue 11 may be provided withbaiiieslii, 13 to cause the gases to pass back and forth through theflue 11.

In the illustrative form, the flue 11 has a top wall 14- and a, bottomWall 15 connected,

with the side walls thereof, the top Wall and the bottom well beingprovided with holes in alinement and extending through the walls. p I

Each pair of oppositely disposed holes is connected by a tube 16 whichpassesthrough the hole-in the top wall 14 and rests on the bottom wall15 concentric with the hole therein. In order to aid in the location ofthe lower end of the tubes 16 in proper relation to the respectiveopenings in the lower wall 15, I preferably-provide a conical cavity 17around each of the holes in the wall 15. Preferably, the upper ends ofthe tubes 16 project beyond the top wall 15 in the manner shown. Thetubes 16 may be a sutlicient- 1y tight fitin the holes in the wall 14-to provide a gas seal, but preferably I provide.

some sealing means which can be readily removed. in the illustrativeform, this sealing means may be a ring 18 of asbestos packing or thelike and if preferred, this ring may be held in place by a packingweight 19, as

shown in Fig. i, the flue wall surrounding the tube preferably beingprovidedwith a conical cavity in which the packing islocateo. asillustrated. The weight of the tubes 16 .will usually be suficient toseal the end thereof with the lower wall 15. H: desired, however, asimilar sealing means can be provided around the lower ends ofthe tubes16.

In the illustrative embodiment, the upper ends of the tubes 16communicate directly as with the air and the lower Wall 15 is providedwitha duct 20 surrounding the lower ends of all of the tubes 16 and theopenings communicating with these tubes through the lower wall 15.

In practice, the hot gases pass into the inlet 10 and flow back andforth across the exterior of-the tubes 16 and out of the outlet 1%. Atthe same time, air is drawn'downward through the tubes 16 by 'asuctiondeas coated with dust which materially interferes'lo with the eiiicicncyof the device. By the ar-- rangement shown, these tubes may be readilybleaned by drawing them out throughthe holes inthe upper wall let. At 16a tube is shown partly lifted, and it will be noted that the exteriorwall of the tube is, in effect, scraped by the edge of the hole in thetop wall 14, which in itself will'u'sually remove the accumulated sootand .dust which will fall to the bottom wall 15mm from thence 8O outthrough the openings therein. If desired,the tube 16 may be entirelywithdrawn 9 for cleaning purposes. On the other hand, f the tube canbe-quickly returned to place, 9

because, particularly when the-sealing aran rangement illustrated isused, the asbestos ring may be placed around the tube as it passesthrough the top-wall 1+1 and, by reason of the conical cavity on theupper surface of that wall, this packing ring will be drawn'fl downsufficiently tightly. into the conical space to seal the exterior of thetube against gas leakage from or, into thefiue 11, and when the bottomof the tube reaches the lower wall 15, theweight ofthe tube will W alsogive, a sufiicient sealing against "the upper surface of this bottomwall. T In order to increase the scraping portion otthe upper wall, Ipreferablymalrethe portion sure rounding each tube n the form of a cone,

Q masses the air tu es, it is obvious that any. other desired shape maybe used. Similarly, while I prefer to utilize the weight of the tubes asa means for sealing themat the bottom, which, of course, necessitatesthat these tubes shall be substantially vertical, it will 'be'obviousthat the tubes may be horizontal,

in which case, some sealing arrangement not dependent on the weight ofthe tube must be used, such as the packing ring illustrated for the topof the tube.

In any case, however, by my invention the tubes are made so to bequickly and readily removed, and to this end, they are only looselyconnected to the heads or walls through which they pass.

While I have described my device as an air heater, it will be understoodthat it may be used for the transfer of heat from any gas to any othergas passing through the res ectivepaths.

y causing the tubes to pass through the openings of one wall with asliding fit, leither with or without the prevention of movement of thetubes through the other v walls in the manner described, the tubes arefree to expand individually or collectively through the openings inwhich they slide. Such an arrangement is particularly useful with an airheater where it is desired to blow from the tubes soot or dust which hascollected therein, and where the steam usually used for this operationcauses a relative expansion of the tubes thus cleaned. Furthermore, byproviding means for sealing the sliding oint and maintained in sealinengagement therewith under both expanded and unex ended conditions 01""the tube in the desori d manner, the tubes maintain a substantially gastight fit under. all conditions of operation.

I claim:

1. In an air heater, a gas flue having an inlet and an outlet and havinga plurality of airs of holes in alinement in its top and ttom walls, andtubes extending vertically across the flue, each tube connecting a pairof said holes and extending into the ole in the top wall with arelatively loose fit and being unconnected thereto, with the lower endof the tube abutting against the interior of the bottom wall of the flueand held there by the weight of the tube, the interior face of the topwall of the flue havingessloped projections surrounding the tu v V 2. Inan air heater, a chamber provided with end walls each provided with aplurality of openings, a plurality of tubes, the openings in one endwall being large enough to permit said tubes to pass through, v

the openings in the other end wall comprising a comically shaped portionand being insufllcientlv large to permit the tubes to pass entirelythrough said end wall the end portions of said tubes co-acting with theopenings in said walls, each tube passingthrough an openingeinone wallwith a sliding fit whereby t tube is free to expand therethrough, andmeans surrounding the tube for sealing said sliding joint and maintainedin sealim en 'a-gement therewith under both ex ended an unexpandedconditions of the tu e.

3. In an air heater, a chamber provided with end walls each providedwith a plurality of openings, a plurality of tubes; the openings in oneend wall being large enough to permit said tubes to pass through, theopenings in the other end wall comprising a conically shaped portion andbeing insuificientl large to ermit the tubes to pass entirely t roughsaid end wall, the end portions'of said tubes coacting with the openingsin said walls, each tube passing through an openin in one wall with asliding fit whereby-t e tube is free to expand there through and heldagainst movement through the other wall, and means surrounding the tubefor sealing said sliding joint and maintained in sealin engagementtherewith under both expan ed and unexpand.ed conditions of the tube. 7

l. In an air heater, a gas flue having an inlet and an outlet andhaving-a plurality of pairs of holes in alinement in its top and bottomwalls, and tubes extending vertically across the flue, each tubeconnecting a pair of said holes and extending into the hole in the topwallwith arelatively loose fit and being unconnected thereto, the holesin said bottom wall being. surrounded by conical cavities with thegreater diameter at the top, the lower ends of said tubes behole, apacking between the tube and the exterior of the wall of theflue, and apacking weight surrounding the tube and resting on said packing toretain the same in position.

'6. In a heat inferchanger, a flue having anfl inlet and. an mltlet andhaving a plurality ofpairs of holes in aiinementin its opposite Walls,tubes extending across the flue, each tube connecting a pair of saidholes and extending into and through at least one. of

said heles with a. relatively loose fit and. bemg unconnected thereto,said tube being adapted to 31% withdrawn through said hole, "the. fine,Wall surrounding the-*tube being form-ed with a camical cafirity a:packing seated, in said conical cavity, "and a papking weightsurrouwiing the tube and resting on said packizig m retaig the same inposition CHARLES J b HANIMAN.

